JP5958163B2 - Conveying member, toner conveying apparatus, and image forming apparatus - Google Patents

Description

  The present invention relates to a conveyance member, a toner conveyance device, and an image forming apparatus.

  In an image forming apparatus such as a copying machine or a printer, toner is used to form an image, and this toner is stored in a toner storage unit. The developing device of the image forming apparatus is provided with a toner transport device for transporting the toner discharged from the toner container to the developing roll. In this toner conveying device, for example, toner is conveyed by a conveying auger provided with a spiral blade as a conveying member (see Patent Documents 1 and 2).

  The toner transported by such a toner transport device is becoming smaller in diameter as the image formation becomes higher in image quality. For example, the toner having a particle diameter of 5.8 μm is further reduced in diameter, The particle size is as small as 3.8 μm.

JP 2008-216360 A Japanese Patent Laid-Open No. 02-197873

  The small-diameter toner as described above is likely to aggregate, and for example, toner that has fallen freely from the toner storage portion may be clogged in the toner receiving portion of the toner conveying device.

  SUMMARY An advantage of some aspects of the invention is that it provides a conveyance member, a toner conveyance device, and an image forming apparatus using the conveyance member that suppress accumulation due to aggregation of toner supplied from a toner storage unit. And

The invention according to claim 1 includes a shaft and a conveying blade spirally provided on the shaft, and the shaft projects a drop path where the toner falls from above in the direction of gravity. Two plate portions provided at positions overlapping with the dropping path, and a through hole, and the through hole is between the two plate portions in a crossing direction intersecting the axial direction of the shaft. It provided a position, the two plate portions, have a shape extending in the tangential direction of the outer peripheral portion of said shaft, a conveying member, characterized in that are arranged at different positions in the tangential direction.

  According to a second aspect of the present invention, a pair of the plate portions are arranged at different positions in the rotational direction of the shaft, the pair of plate portions are substantially parallel to each other, and the through hole is provided between the pair of plate portions. The conveying member according to claim 1, wherein: is formed.

According to a third aspect of the present invention, there is provided a toner containing portion for containing toner, a toner receiving portion for receiving toner supplied from a dropping path through which the toner from the toner containing portion falls, two plate portions and a through hole And a through blade provided in a spiral shape on the shaft, and the through hole extends between the two plate portions in a crossing direction intersecting the axial direction of the first shaft. The two plate portions have a shape extending in a tangential direction of the outer peripheral portion of the first shaft , and a first transport member disposed at a different position in the tangential direction ; and wherein the the two plate portions and the through hole, the dropping path when viewed as projected from the direction of gravity above, in the toner conveying device, wherein the provided octopus at a position overlapping with respect to the dropping path is there.

  According to a fourth aspect of the present invention, a pair of the plate portions are disposed at different positions in the rotation direction of the first shaft, the pair of plate portions are substantially parallel to each other, and are disposed between the pair of plate portions. The toner conveying device according to claim 3, wherein the through hole is formed.

  According to a fifth aspect of the present invention, the second conveying member having the second shaft provided with the spiral second blade and the toner pushed out by the plate portion are received, and the second conveying member receives the second conveying member. The toner conveying device according to claim 3, further comprising a delivery unit that moves toward the toner.

  According to a sixth aspect of the present invention, the apparatus includes a merging unit that merges the toner moved from the transfer unit to the second conveying member and the developer supplied from the first conveying member. The toner conveying device according to claim 5.

  A seventh aspect of the invention includes a developing device using the toner conveying device according to any one of the third to sixth aspects, and forms an image on the supplied recording medium. The image forming apparatus.

According to the first aspect of the present invention, it is possible to provide a conveying member capable of suppressing the accumulation due to toner aggregation as compared with the case where the present configuration is not provided.
According to the second aspect of the present invention, it is possible to provide a conveying member that can further suppress accumulation due to toner aggregation as compared with the case where the present configuration is not provided.
According to the third aspect of the present invention, the toner can be pushed out from the toner receiving portion even when the toner has a large angle of repose and is easy to agglomerate as compared with the case without this configuration. A toner conveying device capable of maintaining stability can be provided.
According to the fourth aspect of the present invention, since the two plate portions are provided, the toner can be pushed out from the toner receiving portion more efficiently and the toner concentration can be stabilized as compared with the case where this configuration is not provided. Therefore, it is possible to provide a toner conveying device that can maintain the property.
According to the fifth aspect of the present invention, there is no clogging of the toner at the toner receiving portion, and the toner can be stably supplied to the transferring portion.
According to the sixth aspect of the present invention, there is no clogging of the toner at the toner receiving portion, and the toner can be stably supplied from the transfer portion to the merging portion.
According to the image forming apparatus of the seventh aspect, the image quality of the output image is improved as compared with the case where the developing device using the toner conveying device according to any one of the third to sixth aspects is not provided. The decrease can be suppressed.

1 is a schematic configuration diagram illustrating an image forming apparatus using a toner conveying device of an embodiment. FIG. 2 is a schematic diagram illustrating a conveyance member and a toner conveyance device according to an embodiment. It is a schematic diagram which shows the board part of embodiment. It is a perspective view which shows a supply auger. FIG. 6 is a schematic diagram illustrating toner accumulation. 6 is a graph showing measurement of toner discharge amount.

(Embodiment)
Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic configuration diagram of an image forming apparatus using a toner conveying device of the present invention. The image forming apparatus 1 according to the embodiment includes a control unit 2, a photoconductor 10, a charging unit 20, an exposure unit 30, a developing device 40 using a toner conveying device 44, a transfer unit 50, a fixing unit 60, a cleaning unit 70, A paper storage unit 80 is provided, and an image is formed on a paper P that is a recording medium based on supplied image information.

The control unit 2 is a CPU (Central
An arithmetic device such as a processing unit) and a memory are provided, and the operation of each component of the image forming apparatus 1 is controlled. The photosensitive member 10 is a cylindrical rotating member having a photosensitive layer formed of an organic photosensitive material for holding an image and rotating in the direction of the arrow shown in FIG.

  The charging unit 20 applies a predetermined charging voltage using a charging roll that rotates in contact with the surface of the photoreceptor 10. The charging unit 20 includes a contact charging method in which the photosensitive member 10 is charged by using a brush or the like, or a non-contact charging method in which the photosensitive member 10 is charged using corona discharge.

  The exposure unit 30 irradiates the surface of the photoconductor 10 charged by the charging unit 20 with light corresponding to image data to form an electrostatic latent image having a latent image potential based on a potential difference. The electrostatic latent image moves to a position where the developing device 40 is disposed as the photoconductor 10 rotates.

  The developing device 40 has a developing roll 41, and the toner adsorbed on the developing roll 41 moves to the photoreceptor 10. This toner moves to the surface of the photoconductor 10 due to a potential difference from the electrostatic latent image formed on the photoconductor 10. In this way, a toner image is formed on the photoconductor 10, and this toner image moves to the transfer unit 50 as the photoconductor 10 rotates.

  Further, toner is supplied to the developing device 40 from a detachable toner container 42 provided above. That is, the toner discharged from the toner container 42 is supplied to the toner conveying device 44 via the toner supply conveying path 43 which is a dropping path while dropping in the direction of gravity. Then, the toner conveying device 44 conveys the toner so as to be supplied to the developing roll 41, for example. Details of the toner conveying device 44 will be described later.

  The transfer unit 50 transfers the toner image formed on the photoconductor 10 onto the paper P conveyed by the conveyance roll 91. The sheet P on which the toner image is transferred is conveyed to the fixing unit 60 by the conveyance roll 91. In the fixing unit 60, an unfixed toner image is pressed and heated by the heating roll 92 and fixed on the paper P. The paper P fixed by the fixing unit 60 is transported and stored by the transport roll 91.

  The cleaning unit 70 removes the toner remaining on the surface of the photoreceptor 10 after the toner image is transferred to the paper P. The paper storage unit 80 stores paper P, which is a plurality of recording media. The paper P is taken out from the paper storage unit 80 by the paper feed roll 90 and conveyed to the transfer unit 50 by the conveyance roll 91.

  Next, the conveyance member and the toner conveyance device 44 according to the embodiment will be described with reference to FIGS. FIG. 2A shows the front surface of the toner conveying device 44, and FIG. 2B shows the plane of the toner conveying device 44. 2A and 2B, the toner conveying device 44 includes a toner receiving portion 44a, a delivery portion 44b, a merging portion 44c, a supply auger 45 as a first conveying member, a first shaft 45a, a first shaft 45a, and a first shaft 45a. A first blade 45 b, an admix auger 46 as a second conveying member, a second shaft 46 a, a second blade 46 b, and a plate portion 47.

  As shown in FIG. 2A, the toner receiving portion 44a is disposed so as to receive the toner T, which is fine powder particles falling from the toner storage portion. That is, the toner T filled in the toner storage unit 42 is discharged from the discharge unit 42 a based on the control of the control unit 2. Then, the discharged toner T is dropped into the toner receiving portion 44a via the toner supply / conveyance path 43 while dropping.

  As shown in FIG. 2 (b), the delivery unit 44 b is disposed so as to deliver the toner T dropped from the toner storage unit 42 to the toner receiving unit 44 a and pushed out by the plate unit 47 to the admix auger 46. Has been.

  The merge portion 44 c is arranged to merge the toner T supplied from the transfer portion 44 b and the developer G including the carrier supplied from the supply auger 45. The toner T and the developer G that are merged and mixed in the merge unit 44 c are conveyed by the admix auger 46.

  The supply auger 45 includes a first shaft 45a that is a rotating shaft and a first blade 45b that is a spiral blade formed on the outer periphery of the first shaft 45a. For example, the first blade 45b conveys the developer G including a carrier and supplies the developer G to the junction 44c. The excess developer G conveyed by the first blade 45 b may be discharged by a trickle discharge unit (not shown) provided at the lower portion of the supply auger 45.

  The admix auger 46 includes a second shaft 46a that is a rotating shaft and a second blade 46b that is a spiral blade formed on the outer periphery of the second shaft 46a. The second blade 46b rotates with the rotation of the second shaft 46a, and conveys the toner T and the developer G mixed in the joining portion 44c.

  As shown in FIG. 2A, the plate portion 47 is formed integrally with the supply auger 45 so as to rotate together with the first shaft 45a. That is, the plate portion 47 is provided at a position overlapping with the extension line in the gravity direction of the dropping path where the toner of the first shaft 45a falls.

  Further, as shown in FIG. 2B, the plate portion 47 is disposed so as to send the toner T dropped into the toner receiving portion 44a to the delivery portion 44b. In other words, when the toner T dropped into the toner receiving portion 44a has a small particle diameter and a large angle of repose, the toner T is deposited on the toner receiving portion 44a. The plate portion 47 is formed so that the toner T is pushed out from the toner receiving portion 44a and fed into the delivery portion 44b so that the toner T does not accumulate.

  Next, the plate portion 47 will be described with reference to FIG. FIG. 3A shows the front surface of the plate portion 47. FIG. 3B shows the plane of the plate portion 47. FIG. 3C shows a cross section taken along line AA in FIG. FIG. 3D shows a cross section taken along line BB in FIG.

  As shown in FIGS. 3A to 3D, the plate portion 47 includes a first plate portion 47a and a second plate portion 47b, which are a pair of plate portions, and joint portions Sa and Sb.

  The 1st board part 47a and the 2nd board part 47b are joined on both sides of the 1st axis | shaft 45a. Further, these plate portions oppose each other at different positions in the rotation direction, and have a through hole K between them.

  The through hole K is provided at a position where the toner T dropped from the toner accommodating portion 42 overlaps the extension line in the gravity direction of the plate portion 47 of the first shaft 45a and the toner dropping path. The first plate portion 47a and the second plate portion 47b are formed so as to push out the toner T entering the through hole K by rotating with the rotation of the first shaft 45a.

  The joint portion Sa is provided at both corners of one end of the first plate portion 47a, and is a portion joined to the first shaft 45a. Further, the joint portion Sb is provided at both corners of one end of the second plate portion 47b and is a portion joined to the first shaft 45a. Such joint portions Sa and Sb are disposed so as to face each other with the first shaft 45a interposed therebetween.

  In this way, the first plate portion 47a is joined to the first shaft 45a at the joint portion Sa, and the second plate portion 47b is joined to the first shaft 45a at the joint portion Sb. By such joining, the first shaft 45a is sandwiched between the first plate portion 47a and the second plate portion 47b and connected to these plate portions.

  Next, the supply auger 45 of the embodiment and the supply auger 145 of the comparative example will be described with reference to FIGS. FIG. 4A is a perspective view showing the supply auger 45 of the embodiment, and each configuration is as described above. FIG. 4B is a perspective view showing a supply auger 145 of a comparative example, and this supply auger 145 has a first shaft 145 a, a first blade 145 b, and a plate portion 147. The supply auger 145 has a plate portion 147 different from the plate portion 47 of the embodiment. In other words, the plate portion 147 is provided on the surface of the first shaft 145a disposed in the toner receiving portion 144a.

  FIG. 5A shows a state where the plate portion 47 suppresses toner accumulation. That is, the first plate portion 47a and the second plate portion 47b rotate in conjunction with the rotation of the first shaft 45a, and push out the toner T that has been dropped into the through hole K, thereby causing the toner T Suppresses deposition.

  FIG. 5B shows a state where toner is aggregated and accumulated on the plate portion 147. That is, since the plate portion 147 does not have the through hole K of the embodiment, the toner T dropped into the plate portion 147 aggregates and accumulates around the first shaft 145a and the plate portion 147. Will end up. In particular, if the toner T has a small diameter and a high angle of repose and is not easily collapsed, the dropped toner T accumulates on the first shaft 145a and the plate portion 147 in a short time to form, for example, a bridge. .

  Next, the graph shown in FIG. 6 will be described. FIG. 6 shows experimental results of the respective toner discharge amounts when the supply auger 45 and the supply auger 145 are used. In this experiment, a hole was made in the bottom of the merging portion 44c, and the discharge amount of the toner T was measured. That is, the discharge rate (g / s) and the discharge amount (g) of the toner T dropped from the hole are measured with respect to the toner T supplied from the toner container 42. The discharge rate is the discharge amount per unit time, g is the gram, and s is the second.

  FIG. 6A is a graph showing the result when the supply auger 45 is used, and FIG. 6B is a graph showing the result when the supply auger 145 is used. The horizontal axis of this graph indicates the number of times of job, which is the number of times the predetermined amount of toner T is supplied, and the number of jobs and the supply amount of toner T are proportional. In addition, the vertical axis of the graph indicates the discharge rate (g / s) and the discharge amount (g) of the toner T.

  In the supply auger 45, as shown in FIG. 6A, even if the number of jobs increases, the discharge rate does not change, and the discharge amount increases in proportion to the number of jobs. From this result, it can be seen that the toner T is not deposited on the toner receiving portion 44a.

  On the other hand, in the supply auger 145, as shown in FIG. 6B, the number of jobs is about 10, the discharge rate becomes zero, and the subsequent discharge amount does not increase. In such a state, it can be said that the toner T is accumulated on the toner receiving portion 144a. From this experimental result, it can be seen that the supply auger 45 having the plate portion 47 is more effective than the supply auger 145 having the plate portion 147.

  The above is the description of the toner conveying device 44 of the embodiment and the image forming apparatus 1 using the same. According to such an embodiment, the pair of (two) plate portions joined to the shaft of the supply auger face each other through the through-holes so that their surfaces are shifted to different positions in the rotation axis direction. Toner accumulation is suppressed by the through holes between the portions. In this embodiment, the surface area of the plate portion is also increased, and the toner carrying capability can be improved.

(Other embodiments)
The above is the description of the toner conveying device of the embodiment and the image forming apparatus using the same, but the present invention is not limited to the above-described embodiment, and other embodiments are possible. Hereinafter, other embodiments will be described.

  In the toner conveying device of the embodiment, the through hole is formed by a pair of plates, but the present invention is not limited to this. For example, the plate portion may include a single plate and a through hole formed in the first shaft.

  In the toner conveying device of the embodiment, a supply auger and an admix auger are used, but the present invention is not limited to this. For example, the toner conveying device using the plate portion of the present invention may not have an admix auger.

  The toner conveying device of the embodiment is used in a developing device that uses a two-component developer as a developer, but is not limited thereto. For example, the toner conveying device of the present invention may be used in a developing device that uses a one-component developer.

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 2 Control apparatus 10 Photoconductor 20 Charging part 30 Exposure part 40 Developing apparatus 41 Developing roll 42 Toner accommodating part 42a Discharge part 43 Toner supply conveyance path 44 Toner conveyance apparatus 44a Toner receiving part 44b Delivery part 44c Merge part 45 Supply Auger 45a First shaft 45b First blade 46 Admix auger 46a Second shaft 46b Second blade 47 Plate portion 47a First plate portion 47b Second plate portion 50 Transfer portion 60 Fixing portion 70 Cleaning portion 80 Paper storage Part 90 paper feed roll 91 transport roll 92 heating roll 144a toner receiving part 145 supply auger 145a first shaft 145b first blade 147 plate part P paper T toner G developer K through holes Sa, Sb joint part

Claims (7)

The axis,
A conveying blade spirally provided on the shaft,
The shaft has two plate portions provided at positions overlapping with the falling path when a falling path in which the toner falls is projected from above in the direction of gravity, and a through hole.
The through hole is provided at a position between the two plate portions in a crossing direction intersecting the axial direction of the shaft,
The two plate portions, have a shape extending in the tangential direction of the outer peripheral portion of the shaft, conveying member, characterized in that are arranged at different positions in the tangential direction. A pair of the plate portions are arranged at different positions in the rotation direction of the shaft, the pair of plate portions are substantially parallel to each other, and the through hole is formed between the pair of plate portions. The conveying member according to claim 1. A toner container for containing toner;
A toner receiving portion for receiving toner supplied from a dropping path through which toner from the toner containing portion falls;
A first shaft having two plate portions and a through hole; and a conveying blade spirally provided on the shaft, wherein the through hole intersects with the axial direction of the first shaft. The two plate portions have a shape extending in the tangential direction of the outer peripheral portion of the first shaft, and are arranged at different positions in the tangential direction. A first conveying member,
Wherein the two plate portions and the through hole, the dropping path when viewed as projected from the direction of gravity above, provided at a position overlapping with respect to the dropping path
Toner transport device comprising a call. A pair of the plate portions are arranged at different positions in the rotation direction of the first shaft, the pair of plate portions are substantially parallel to each other, and the through hole is formed between the pair of plate portions. The toner conveying device according to claim 3, wherein A second transport member provided with a spiral second blade on the second shaft;
A transfer section that receives the toner pushed out by the plate section and moves toward the second transport member;
The toner conveying device according to claim 3, wherein the toner conveying device is provided.   6. The toner transport according to claim 5, further comprising a joining unit that joins the toner moved from the transfer unit to the second transport member and the developer supplied from the first transport member. apparatus.   An image forming apparatus comprising: a developing device using the toner conveying device according to claim 3, and forming an image on a supplied recording medium.

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